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`include "gfx/gfx_defs.sv"
module gfx_fifo_overflow
#(parameter DEPTH=0)
(
input logic clk,
rst_n,
input logic down,
out_ready,
out_valid,
output logic empty,
down_safe
);
logic up;
logic[$clog2(DEPTH + 1) - 1:0] pending;
assign up = out_ready && out_valid;
assign empty = pending == 0;
assign down_safe = up || pending < DEPTH - 1;
always_ff @(posedge clk or negedge rst_n)
if (!rst_n)
pending <= 0;
else begin
if (up && !down)
pending <= pending - 1;
else if (!up && down)
pending <= pending + 1;
end
endmodule
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